John, I re-read your question
Would it be possible (only using machinery, equipment and supplies normally in an MOW or wreck/work train) to jury rig the necessary lines to pull a business car behind a flat car?
Your mention of jury-rigging makes me think that there is something wrong with the passenger car, and the first thing that comes to mind is inoperative brakes.
In a real railroad situation, when a car has been in a wreck and has inoperative brakes that cannot be repaired on-site, and must be moved to a repair location, a long hose is coupled to the brake pipe hoses of the cars ahead of and behind the defective car. The hose is attached on the outside, along the length of the defective car. It is imperative that cars with operative air brakes be coupled ahead of and behind the car with defective brakes. Normally there is a speed restriction. Such a car would almost never be accepted from a shipper for movement. If accepted, it would not be moved farther than the nearest repair facility. Except for cars having been badly wrecked, brake equipment should be able to be repaired in the field and no jury-rigging should be allowed. On my Home Road (Santa Fe) wrecked passenger cars were sometimes moved this way to Topeka, Kansas, where the System Passenger Car Shop was located, but done at great expense in special trains, with constant Mechanical and Operating Department supervision.
If there is a draft gear problem, it will have to be repaired before movement. Railroads will chain up a car that suffers broken draft gear en route, to move it to the nearest setout track, but not for through movement. In order to use a chain there has to be something there to which you can attach the chain.
If this is about moving an old passenger car with defects for a museum association, the railroad might work with you. If you have bought a passenger car with defects to move off-site for other use, you'll probably need to have it moved all the way on a lowboy truck.
Special movements such as I have described tie up a lot of Mechanical Department people and Operating Department officials whose normal jobs are somewhere else and are not being done while the special movement is in progress. You can understand how this will make a railroad reluctant to have anything to to with such movements.
